just to update this thread...........
the first batch of 2.5" backboxes all died an early death
Piper have redesigned the backbox and now it has a 29" long repackable silencer
my original lasted just 300 miles before the silencing material left via the tail pipes, hopefully the new design will last a little longer :silent:
Garry has also left Piper, so Tom is now dealing with these.